Light-sensitive silver halide color photographic emulsion

ABSTRACT

A COLOR PHOTOGRAPHIC EMULSION CONTAINING A COLOR FORMER OF THE FORMULA:   1-(X1,X2,X3-PHENYL),3-R1,5-(O=)-2-PYRAZOLINE   AND AT LEAST ONE COMPOUND OF THE FORMULA:   A-CH(-B)-X4 OR X5-CH&lt;(-CO-F-)   WHEREIN R1 IS ALKYL, ACYLAMINO RO SULFONAMIDO; X1,X2 AND X3 ARE HYDROGEN, ALKYL, HALOGEN, ACYLAMINO, ALKYLCARBAMOLY, SULFONAMIDO, SULFAMOYL, ALKOXY OR ARYLOXY; A AND B ARE -COR2, -COOR2&#39;&#39;, -CONHR2&#34; OR -CN; R2, R2&#39;&#39;,R2&#34;, X4 AND Y5 ARE ALLYL, ALKYL, ARYL, CYCLOALKYL OR ARAKYLY AND F IS AN ATOM OR RADICAL NECESSARY TO FORM A PYRAZOLONE RING.

United States Patent 01 Ffice 3,580,722 Patented May 25, 1971 Int. or.dine 1/40 US. Cl. 96-100 6 Claims ABSTRACT OF THE DISCLOSURE A colorphotographic emulsion containing a color former of the formula:

and at least one compound of the formula:

\CHX4 ,00 r: gHX&

wherein R is alkyl, acylamino or snlfonamido; X X and X are hydrogen,alkyl, halogen, acylamino, alkylcarbamoyl, sulfonamido, sulfamoyl,alkoxy or aryloxy; A and B are -C0R COOR CONHR or CN; R R R X and X areallyl, alkyl, aryl, cycloalkyl or araklyl and F is an atom or radicalnecessary to form a pyrazolone ring.

This invention relates to a light-sensitive silver halide colorphotographic emulsion capable of forming a color image by colordevelopment. In particular, the invention relates to a colorphotographic emulsion containing a pyrazolone derivative as a magentacolor former.

More particularly, the color photographic emulsion contains at least oneof the color formers of the general Formula I and at least one of thecompounds of the general Formulas II and IH.

In the above formulas.

R is an unsubstituted or substituted alkyl, acylamino or sulfonamidogroup;

X X and X; which may be the same or different are hydrogen,unsubstituted or substituted alkyl, halogen, acylamino, unsubstituted orsubstituted alkylcarbamoyl, sulfonamido, unsubstituted or substitutedsulfamoyl, alkoxy or aryloxy group;

A and B are COR COOR C0NHR or CN; R R R X and X are substituted orunsubstituted allyl, alkyl, aryl, cycloalkyl or aralkyl groups; and

F represents an atom or radical necessary for forming a pyrazolone ring.

As the result of various investigations on the silver halidephotographic emulsions containing a color former, it is known that alight-sensitive photographic material prepared from a silver halidephotographic emulsion containing only a color former with low couplingreactivity, when treated by a developing solution consisting principallyof a p-phenylenediamine derivative, readily produces a linear gradation,but the speed of development is delayed on account of low couplingreactivity and the density is insuflicient. Consequently the contrast ofthe resulting image is low and suflicient photographic sensitivity isnot obtainable. In order to overcome the above disadvantages, it hasbeen proposed to increase the quantity of the color former and silverhalide or to increase the thickness of the emulsion layer. As is Wellknown, however, both of the above improvements have serious drawbacksand the dis advantages as aforementioned cannot satisfactorily be solvedthereby. More particularly, an increase in the quantity of the colorformer and silver halide results in a considerable increase in viscosityof the emulsion and coating of such emulsion on a support is difficult.Further, such an emulsion is very readily fogged and is inferior instability of photographic properties. On the other hand, an increase inthe thickness of the emulsion layer results in depression of thesharpness of the resulting images on account of halation, inadiation andother factors.

Under the circumstances, a combination comprising a color former showinglow coupling reactivity and a color former showing relatively highcoupling reactivity has been proposed. The drawbacks of theaforementioned prior processes are somewhat improved with saidcombination. However, mixing of the developed dyes is caused by thecombination of two or more of the different color formers so that anundesirable color shift occurs. This makes it impossible to use theemulsion for color photography, consequently.

Now, according to the present invention, it has been found that at leastone of the color formers of the above general Formula I which shows lowcoupling reactivity is added to a silver halide photographic emulsion incombination with at least one of the compounds of the general FormulasII and III which reacts with an oxidation product of p-phenylenediaminederivative to form a colorless coupling product. The resulting emulsiondoes not suffer from any change of spectral absorption characteristic ofthe developed dyes and, what is more, the speed and gamma values areextremely increased.

Thus, according to the silver halide color photographic emulsion havingincreased speed and gamma values of this invention, a small amount ofthe color former is suflicient and the viscosity of the emulsion isdecreased and consequently, coating of the emulsion on a support caneasily be made. Further, such an emulsion is safe from fogging and thethickness of the emulsion layer is reduced. With such an emulsion, alight-sensitive color photographic material having improved sharpness ofthe resulting image may be obtained.

Typical color formers of the general Formula I are as 2H5 s u 01 fif f IN C 0 HOOO-CHCHzCONH C H -CHO ONH-C-OH2 s OzN (CH3) 3 CmHar-CHC ONH-CCH2HO O OCH2(|3|CH2 NHC O CHr-CH-CNHN Typical compounds of the generalFormula II are as follows:

CN?HC 0 -NHCOCHz(3HC1aHa1 CH3 0 0 0 H l N N l N NH N 0311 1 I Typicalcompounds of the general Formula III are as (EH3 follows: H C O OH(III-1) H C 7H35-CCHCH3 18 37 111 J30 S 03H (III-l0) CH3 N 0 CH3 (III 3)(EH-{300E C17H35C-CHC2H5 0 It should be understood that the color formerof the I general Formula I and the compounds of the general Formulas IIand HI used in this invention are not limited to those exemplifiedabove, and alkali metal salts or ammonium salts of the sulfonic acid orcarboxylic acid of the general Formulas I and II or III are includedwithin the scope of the present invention. (up!) Addition of at leastone color former of the general CUHSS C CHCHZCI Formula I and at leastone of the compounds of the ll I 0 general Formulas II and III to thephotographic emulsion may be made either directly in the form of anaqueous alkali solution such as sodium hydroxide or in the form of adispersion prepared by dissolving the color former of the generalFormula I and the compounds of general Formulas II, III in a low boilingorganic solvent such as butyl alcohol and butyl acetate and a highboiling organic solvent such as dibutyl phthalate, mixing the re- I SOKHsulting solution with a gelatine solution containing a surface activeagent and then treating the mixture in a colloid mill. Alternatively,addition may be made by means of a known dispersion method. Each of thecompounds of the general Formulas H and III is used in a molar ratio of005-1 to the color former of the general Formula I, particularly a molarratio in the range of 0.1-0.5 is effective.

For the photographic emulsion of the present invention, various silverhalide emulsions such as silver chloride-, silver bromide-, silveriodideand silver chlorobromide emulsions are usable and these emulsionsmay further contain a chemical sensitizer such as sulfur-, reduction-,or noble metal-sensitizer and an optical sensi tizer and, in addition,various additives, for example, a fog inhibitor, a stabilizer, ananti-stain agent, 2. developing accelerator, a hardening agent and acoating aid, etc.

Further, when optically sensitized emulsions are coated in the sameplace in two layers, the color former of the general Formula I and thecompounds of the general Formulas I and II are applicable to either orboth of such emulsions.

This invention will be explained in more detail by the followingexamples wherein all parts given are by weight:

EXAMPLE 1 To 100 parts of a light-sensitive gelatino silver bromoiodideemulsion prepared by a conventional manner and containing a greensensitive optical sensitizer are added, a aqueous alkali solution of thecolor former (I7) and a 5% aqueous alkali solution of the compound(III-2) or (III-4) in the amounts indicated in the Table 1 below. Thethus treated emulsion is coated on a film base. The resulting film isthen treated at 20 C. for minutes with a developing solution comprisingas the principal color developer N,N-diethyl-p-phenylenediamine andthereafter subjected to bleaching and fixing. Increase of the density isshown in Table 1 by way of the photographic gamma value measured byusing green light density. The emulsions of this invention exhibitremark- EXAMPLE 2 A similar film is prepared in the same manner as inExample 1 by using a 5% aqueous alkali solution of the color former (I7)and a 5% aqueous alkali solution of compound (III-1) in the amountsindicated in the Table 2 below, respectively. The resulting film is thentreated in the same manner as in Example 1. Gamma values as measured areshown in Table 2. As is obvious from Table 2, the emulsions of thisinvention exhibit remarkable increases in gamma values.

TABLE 2 Compound Color former I III Gamma I7 (21).. III-1 (0) 0 36 I7(21.5)-

III-1 (0) 0 38 I7 (22).. III-1 (0) 0 40 I7 III1 (1) 0.46 I7 (20g III-1(1.5)- 0 50 I7 (20 III-1 (2) 0 68 NOTE.-Flg\1r8s in parentheses areparts.

EXAMPLE 3 Three mixtures, each comprising 1 part of the color former(I8) and l, 1.5 or 2 parts of the compound (III-5), respectively, areseparately dissolved in 3 parts of ethyl acetate by heating. Each of theresulting solutions is added with 1 part of dibutyl phthalate. Thesolution thus obtained is then mixed with 10 parts of an aqueous 10%gelatine solution and passed through a colloid mill to form the colorformer dispersion. The same amount of this dispersion as that used inExample 1 is added to an emulsion containing an adjusted amount ofgelatine to give the same gelatine content as of Example 1 in thefinished total emulsion. Photographic gamma values observed with a filmprepared and treated in a similar manner to that in Example 1 are shownin Table 3.

TABLE 3 Compound Color former I III NOTE.Figures in parentheses areparts.

As is obvious from Table 3, the emulsions of this in- 'vention haveremarkably increased gamma values.

EXAMPLE 4 A similar emulsion as used in Example 1 is prepared by addinga 5% aqueous alkali solution of the color former (I7) and a 5% aqueousalkali solution of the compound (II-1) each in the amounts indicated inTable 4, in which photographic gamma values observed with a filmprepared and treated in a similar manner to that in Example 1 are shown.

TABLE 4 Compound Color former I III Gamma I7 (21) II-1 (0) 0. 26 0.27

N oTE.Figures in parentheses are parts.

As is obvious from the above table, the emulsions of this invention haveoutstandingly increased gamma values.

EXAMPLE 5 A similar emulsion as used in Example 1 is prepared by addinga 5% aqueous alkali solution of the color former (I7) and a 5% aqueousalkali solution of the compound (II-5) each in the amounts indicated inTable 5, in which photographic gamma values observed with a filmprepared and treated in the same manner as in Example 1 are shown.

TABLE 5 Compound Color former I lII Gamma NOTE .-Figures in parenthesesare parts.

I together with at least one of the compounds of the general Formulas IIand III;

wherein,

R represents an alkyl, acylamino or sulfonamido group;

X X and X which are same or difierent represent hydrogen, an alkyl,halogen, acylamino, alkylcarbamoyl, sulfonamido, sulfamoyl, alkoxy oraryloxy group;

A and B represent COR COOR CONHR or R R R X and X represent allyl,alkyl, aryl, cycloalkyl or aralkyl group;

F represents an atom or radical necessary to form a pyrazolone ring. 2.A silver halide color photographic emulsion as claimed in claim 1,comprising the color former of the formula,

-GONHCCH2 it l I o o CtaHas-CHCONH N/ 01 (I-7) in combination with acompound of the formula,

lH31-C ONH-O-CHCH;

SOaH 1 or r 11 as(3-(|3HGH C1 3. A silver halide color photographicemulsion as claimed in claim 1, comprising the color former of theFormula I-7 in combination with the compound of the formula,

(III-1) 4. A silver halide color photographic emulsion as claimed inclaim 1, comprising the color former of the formula,

5. A silver halide color photographic emulsion as claimed in claim 1,comprising the color former of the Formula L7 in combination with thecompound of the formula,

elven-0o-Q-rmooomcnmm CH3 000E (II-1) 6. A silver halide colorphotographic emulsion as claimed in claim 1, comprising the color formerof the Formula I-7 in combination with the compound of the formulanooo-on-ornoorrm-Q-ooon-com1 References Cited FOREIGN PATENTS 721,5201/1955 Great Britain 96-100 J. TRAVIS BROWN, Primary Examiner U.S.Cl.X.R.

